Compare arrays as (multi-) sets

Question

I\'m looking for an efficient way to find out whether two arrays contain same amounts of equal elements (in the == sense), in any order:

foo = {         


        

Answer 1

Thanks everyone for sharing ideas! I've came up with the following

function sameElements(a, b) {
    var hash = function(x) {
        return typeof x + (typeof x == "object" ? a.indexOf(x) : x);
    }
    return a.map(hash).sort().join() == b.map(hash).sort().join();
}

This isn't the fastest solution, but IMO, most readable one so far.